Emergency crews respond to the scene where a ride malfunctioned Thursday night at the North Carolina State Fair in Raleigh, N.C. Several people were sent to the hospital with unknown injuries. (ASSOCIATED PRESS / WNCN, Alison Blevins)

RALEIGH, N.C. (AP) — An accident occurred on a ride at the North Carolina State Fair on Thursday night, sending five people to the hospital with unknown injuries.

The accident on the “Vortex” ride, which spins, twirls and flips passengers upside down, happened about 9:17 p.m., said State Fair spokesman Brian Long. He said an ambulance was on the scene immediately, and that two of the injuries “appear to be serious; the other three not as serious.”

A preliminary investigation indicated that the passengers were injured when the ride started up again as they were getting off, Long said.

The injured riders ranged in age from 14 to 39, Wake County Sheriff Donnie Harrison told a news conference. Linda Fowler, clinical administrator for WakeMed in Raleigh, confirmed that five people were admitted to the hospital from the fair, but did not give out further information.

Long said the ride would undergo inspection by the N.C. Department of Labor, and that the sheriff’s office would also conduct its own investigation and look for witnesses.

Television station WRAL in Raleigh quoted witnesses as saying that several people were thrown off the ride and that some were unconscious.

A witness identified as Caleb Norris told WNCN television that he heard a crashing sound just after getting off the Vortex. He turned around and saw two people lying face down. Norris also said he saw the ride operator fall to his knees and start crying.

The accident occurred shortly before the fair was shutting down for the night. Long said the fair would reopen on Friday as scheduled. It closes Sunday.

In 2002, a ride operator at the fair was killed when he was struck by the ride while it was still in operation.